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Characteristics of chlorine isotope distribution and analysis on sylvinite deposit formation based on ancient salt rock in the western Tarim Basin

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Science china Earth sciences 2005年第11期48卷 1913-1920页

作者： TAN Hongbing1,2. MA Haizhou1, XIAO Yingkai1, WEI Haizhen1,2. ZHANG Xiying1 & MA Wandong1 1. Institute of Salt Lakes, chinese academy of {2., Xining 810008,{3. 2. graduate School of the chinese academy of {2., Beijing 100039,{3. 1. Institute of Salt Lakes Chinese Academy of Sciences 810008 Xining China 2. graduate School of the chinese {2. of {3. 100039 Beijing China

During formation of the Tarim Basin, there repetitively happened seawater invasion for it was ever connected with wide Paleo-mediterranean Sea. At the same time, for the applica-tion of tectonic and paleoenvironmental condition, the basin deposits many sequences of thick strata of evaporites, especially in its two largest subbasins of Kuqa in the north and Shaqa in the southwest. Therefore, the western Tarim Basin has been considered to be a favorable location to prospect ancient sylvinite deposit. But it is unfortunate that the Br×103.Cl ratio, as a common geochemical index to uncover clues of sylvinite deposit, is almost invalid to indicate the stage of ancient brine condensation for very low content of bromine in salt rock samples (less than 10?6 commonly) in the western Tarim Basin evaporites. Fortunately, we noticed recently that the val-ues of chlorine isotope (δ 3.Cl value) for salt rock samples follow some clear laws from place to place, which in the Shaqa subbasin, all δ 3.Cl values of salt rock samples behaved negatively and on the contrary, they all surprisingly showed positive values in the Kuqa subbasin. Based on conclusions of previous research and referring to the ratios of Br×103.Cl for salt rock or brine samples, we proved that the chlorine isotope (δ 3.Cl) could be used as an effective index to find ancient sylvinite deposit in those evaporites rock basin with low content of Br element back-ground, such as the Tarim Basin. Thus according to the new index of chlorine isotope, we con-clude that the concentration of ancient brines formed ancient salt rocks is much more concen-trated in the Shaqa subbasin than that in the Kuqa subbasin. Particularly, the δ 3.Cl value of salt rock in Kashi depression of the western Shaqa subbasin is greatly negative (

关键词： the Tarim Basin, chlorine isotope, ancient salt rock, ancient sylvinite deposit, deposit stage

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A unified dynamic model for locomotion and manipulation of a snake-like robot based on differential geometry

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Science china(Information sciences) 2011年第2期54卷 318-333页

作者： WANG ZhiFeng1,3. MA ShuGen1,2. LI Bin1 & WANG YueChao1 1State Key Laboratory of Robotics, Shenyang Institute of Automation, chinese {2. of sciences, Shenyang 110016,{3. 2.epartment of Robotics, Ritsumeikan university, Shiga-ken 52.-8577, Japan 3.5} university of chinese {2. of sciences, Beijing 100039,{3. 1. State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China3. Graduate University of Chinese Academy of Sciences Beijing 100039 China2. Department of Robotics Ritsumeikan University Shiga-ken 525-8577 Japan

A snake-like robot, whose body is a seried-wound articulated mechanism, can move in various environments. In addition, when one end is fixed on a base, the robot can manipulate objects. A method of dynamic modeling for locomotion and manipulation of the snake-like robot is developed in order to unify the dynamic equations of two states. The transformation from locomotion to manipulation is a mechanism reconfiguration, that is, the robot in locomotion has not a fixed base, but it in manipulation has one. First, a virtual structure method unifies the two states in mechanism (e.g., an embedding in the configuration space); second, the product-of-exponentials formula describes the kinematics; third, the dynamics of locomotion and manipulation are established in a Riemannian manifold; finally, based on the analysis of the dynamic model, the dynamics of manipulation can be directly degenerated from those of locomotion, and this degeneration relation is proved through using the Gauss equations. In the differential geometry formulation, this method realizes the unification of the dynamics of locomotion and manipulation. According to a geometrical point of view, the unified dynamic model for locomotion and manipulation is considered as a submanifold problem endowed with geometric meaning. In addition, the unified model offers an insight into the dynamics of the snake-like robot beyond the dynamic model separately established for locomotion or manipulation.

关键词： snake-like robot dynamics unified model differential geometry locomotion manipulation

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Impact Assessment and Protection of Outstanding Landscape Integrity in a Natural Heritage Site:Fairy Valley,Kanas Nature Reserve,Xinjiang,china

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Journal of Mountain Science 2011年第1期8卷 46-52页

作者： HAN Fang1,2.YANG Zhaoping1,LIU Xinyu1,2.DI Feng3.1 Xinjiang Institute of Ecology and Geography,chinese {2. of sciences,Urumqi 83.011,{3. 2.graduate university of chinese {2. of sciences,Beijing 100049,{3. 3.Xinjiang Department of Science and Technology,Urumqi 83.011,{3. Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China graduate university of {2. {3. of sciences Beijing China Xinjiang Department of Science and Technology Urumqi China

The essential purpose of the Convention Concerning the Protection of World Cultural and Natural Heritage is to protect the integrity of heritage *** landscape is the core embodiment of the aesthetic value of a natural heritage *** paper proposes a new assessment method from the point of view of the protection of heritage *** is used to measure the degree of outstanding landscape integrity under the human and natural impact in natural heritage *** paper employ three indices,a visual index of outstanding landscape,a harmony index of the artificial landscape and a disturbance index of damaged landscape,to measure the impact of landscape *** impact assessment model is based on a weighted combination of the three *** study site is the Fairy Valley,Kanas Nature Reserve,Xinjiang Uygur Autonomous Region in northwest *** information employed is derived from field investigation and a Digital Elevation Model(DEM).A comprehensive evaluation of the Fairy valley was undertaken and it was determined that the outstanding landscape values are being *** protection methods are proposed to reduce the adverse effects and maintain landscape quality,thereby providing site managers with suggestions for the protection of natural heritage *** broadly,the paper contributes novel methods of landscape assessment applicable to natural protected areas.

关键词： Landscape integrity Landscape impact assessment Landscape protection Natural heritage site Kanas Nature Reserve Xinjiang

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Synthesis of well-defined functional PE graft copoly-mers via ATRP process

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Science Bulletin 2005年第10期50卷 1048-1051页

作者： CAO Chengang1, 2. DONG Jinyong1 & HU Youliang1 1. CAS Key Laboratory of Engineering Plastics, Joint Laboratory of Polymer Science and Materials, Institute of Chemistry, chinese academy of {2., Beijing 100080,{3. 2. graduate School, chinese academy of {2., Beijing 100039, {3. CAS Key Laboratory of Engineering Plastics Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China graduate School Chinese Academy of Sciences Beijing 100039 China

In summary, we have demonstrated a convenient yet highly efficient method forthe preparation of PE-based graft copolymers via ATRP.. By introducing a small amount of styrenegroups into PE chains via the selective copolymerization of ethylene with 1,4-divinylbenzenecatalyzed by Et(Ind)_2.rCl_2.MAO, the multifunctional ATRP initiator of1-chloroethylbenzene-containing PE was readily achieved by a quantitative hydrochlorination reactionand was shown to be very effective for the initiation of graft polymerization of MMA and styrene toprepare structurally well-defined PE-based graft copolymers.

关键词： ATRP Synthesis of well-defined functional PE graft copoly-mers via ATRP process PE well

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Pre-irradiation with low-dose ^(12.C^(6+) beam significantly enhances the efficacy of AdCMV-p53.gene therapy in human non-small lung cancer

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Science china(Physics,Mechanics & Astronomy) 2007年第2期50卷 221-230页

作者： LIU Bing1,2.ZHANG Hong1,LI WenJian1,LI Qiang1,ZHOU GuangMing1,XIE Yi1,2.HAO JiFang1,MIN FengLing1,2.ZHOU QingMing1,2.& DUAN Xin1,2. Institute of Modern Physics,chinese academy of {2.,Lanzhou 73.000,{3. 2.graduate university of chinese academy of {2.,Beijing 100039,{3. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000China

The combination of ionizing radiation and gene therapy has been investigated. However, there are very few reports about the combination of heavy-ion irradiation and gene therapy. To determine if the pre-exposure to low-dose heavy ion beam enhances the suppression of AdCMV-p53.on non-small lung cancer (NSLC), the cells pre-irradiated or non-irradiated were infected with 2., 40 MOI of AdCMV-p53. Survival fraction and the relative biology effect (RBE) were determined by clonogenic assay. The results showed that the proportions of p53.positive cells in 12.6+ beam induced AdCMV-p53.infected cells were more than 90%, which were signifi-cantly more than those in γ-ray induced AdCMV-p53.infected cells. The pre-exposure to low-dose 12.6+ beam significantly prevented the G0/G1 arrest and activated G2.M checkpoints. The pre-exposure to 12.6+ beam significantly improved cell to apoptosis. RBEs for the 12.6+ + AdCMV-p53.infection groups were 3.%-60%, 2.%-13.% and 3.%-70% more than those for the 12.6+-irradiated only, AdCMV-p53.infected only, and γ-irradiation induced AdCMVp53.infected groups, respectively. The data suggested that the pre-exposure to low-dose 12.6+ beam significantly promotes exogenous p53.expression in NSLC, and the suppression of AdCMV-p53.gene therapy on NSLC.

关键词： heavy-ion beam gene therapy p53 non-small lung cancer adenoviral vector low dose

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Nitrogen isotopic geochemical characteristics of crude oils in several basins of china

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Science china Earth sciences 2005年第8期48卷 1211-1219页

作者： CHEN Chuanping1,2. MEI Bowen1 & CAO Yacheng3.1. Jianghan Petroleum university, Jingzhou 43.100, china 2. Huazhong university of Science and Technology, Wuhan 43.047, china 3. Nanjing Institute of Soil Science, chinese academy of sciences, Nanjing 2.0008, china 1. Jianghan Petroleum university 434100 Jingzhou China 2. Huazhong university of Science and Technology 430047 Wuhan China 3. Nanjing Institute of Soil Science Chinese Academy of Sciences 210008 Nanjing China

Nitrogen isotopic ratios of crude oils with different physical and chemical properties in several basins of china have been measured and their geochemistry has been studied ele-mentally combined with molecular organic geochemistry methods. The data indicate that δ 15N is in the range of ?6‰-2.‰. They vary with the oils in different sedimentary types of basins. The oils forming in the limnic environment have lower δ 15N with the value of about 1‰-5‰ whereas the oils in saline or semi-saline environment have higher δ 15N, with most samples being above 10‰ and some exceeding 17‰. The average nitrogen isotopic ratio of oils from the Ordovician formation in the Tarim Basin is the lowest, with most samples having δ 15N below zero, which reflects possibly the characteristic of the oils originating mainly from the organic matter formed in marine carbonate sedimentary environment. The δ 15N distribution can be altered by fractionation. It increases obviously because of biodegradation and decreases during hydrocarbon migration. However, the effect of nitrogen isotopic fractionation in the short distance migration is uncon-spicuous.

关键词： nitrogen isotope, crude oil, sedimentary environment, isotopic fractionation, china.

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Explicit analytical solutions of the anisotropic Brinkman model for the natural convection in porous media(Ⅱ)

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 422-430页

作者： CAI Ruixian1, GOU Chenhua1, 2.& ZHANG Na1 1. Institute of Engineering Thermophysics, chinese academy of {2., Beijing 100080,{3. 2. graduate School, chinese academy of {2., Beijing 100080,{3. 1. Institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. graduate School Chinese Academy of Sciences 10080 Beijing China

Some algebraically explicit analytical solutions are derived for the anisotropic Brinkman model―an improved Darcy model―describing the natural convection in porous media. Besides their important theoretical meaning (for example, in analyzing the non-Darcy and anisotropic effects on the convection), such analytical solutions can be the benchmark solutions that can promote the development of computational heat and mass transfer. Some solutions considering the anisotropic effect of permeability have been given previously by the authors, and this paper gives solutions including the anisotropic effect of thermal conductivity and the effect of heat sources.

关键词： explicit analytical solution, porous medium, natural convection, Brinkman model, anisotropic.

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Mechanism and Defense on Malicious Code

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Wuhan university Journal of Natural sciences 2005年第1期10卷 83-88页

作者： WEN Wei-ping 1,2.3. QING Si-han 1,2.3.1. Institute of Software, the {2. academy of sciences, Beijing 100080,{3. 2.Engineering Research Center for Information Security Technology, the {2. academy of sciences, Beijing 100080,{3. 3.graduate School of the {2. academy of sciences, Beijing 100080,{3. Institute of Software the Chinese Academy of Sciences Beijing 100080 China

With the explosive growth of network applications, the threat of the malicious code against network security becomes increasingly serious. In this paper we explore the mechanism of the malicious code by giving an attack model of the malicious code, and discuss the critical techniques of implementation and prevention against the malicious code. The remaining problems and emerging trends in this area are also addressed in the paper.

关键词： malicious code attacking model mechanism defense system security network security

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Modeling of elastic wave propagation on a curved free surface using an improved finite-difference algorithm

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Science china(Physics,Mechanics & Astronomy) 2004年第5期47卷 633-648页

作者： WANG Xiuming1,3.& ZHANG Hailan2.1. CSIRO Petroleum, ARRC, PO BOX 113., Technology Park, Bentley, WA 6102. Australia 2. Institute of Acoustics, {2. academy of sciences, Beijing 100080,{3. 3. Present address: Institute of Acoustics, {2. academy of sciences, Beijing 100080,{3. 1. CSIRO Petroleum ARRC Technology Park PO BOX 1130 6102 Bentley WA Australia 2. Institute of Acoustics Chinese Academy of Sciences 100080 Beijing China

Based on existing direct and imaging methods of a staggered finite-difference scheme, an improved algorithm for staggered finite-difference is proposed to implement rugged topographic free boundary conditions. This method assumes that the free surface can be implemented with horizontal and vertical free surface segments and their corners; the free surface passes through the grid points of shear stress components, instead of the normal stress components. Imaging is carried out for stress components in both horizontal and vertical directions, thus increasing the accuracy. To update particle- velocities, imaging and updating are first performed in the horizontal direction, and then in the vertical direction. The numerical results for elastic flat horizontal free surface with the imaging method and those for flat free surfaces of various slope angles with the proposed method are compared, and are shown to be in good agreement. The advantage of the proposed method is that only the stresses are dealt with in implementing the free surface into the staggered algorithm, which improves computation efficiency.

关键词： elastic wave simulation, curved free surface, staggered finite-difference, algorithm stability.

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Quaternary marine transgressions in eastern china

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Journal of Palaeogeography 2012年第2期1卷 105-125页

作者： Lin Jingxing1, 3. Dai Luping2. 3.1. Institute of Geology, {2. academy of Geological sciences, Beijing 10003.,{3. 2. Key Laboratory of Marine Ecology and Environmental sciences, Institute of Oceanology, {2. academy of sciences, Qingdao 2.6071,{3. 3. College of Earth Science, graduate university of {2. academy of sciences, Beijing 100049,{3. Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Marine Ecology and Environmental sciences Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

Based on the data from 117 holes (9151 samples) and the research on ecology and palaeoecology of Foraminifera combined with that on Ostracoda, diatoms, pollen and spores, eight marine transgressions have been recognized in the great plain regions through the Quaternary sequences and two marine transgressions have been found since the Late Pleistocene in the coastal plain (bedrock coast) areas. In the North china Plain, these are in ascending order:the Bohai transgression in the Early Pleistocene, the Haixing and Huanghua transgressions in the Middle Pleistocene, the Baiyangdian and Cangzhou transgressions in the Late Pleistocene, and the Tianjin transgression in the Holocene. In the Yangtze River Delta region the Rugao and Zhoupu transgressions occurred in the Early Pleistocene, the Shanghai, Jiading, and Wangdian transgressions in the Middle Pleistocene, the Jiangyin and Ge Hu transgressions in the Late Pleistocene, and the Zhenjiang transgression in the Holocene. In the coastal plain (bedrock coast) areas of North china, the Cangzhou transgression was recorded in the Late Pleistocene and the Tianjin transgression in the Holocene, whereas in South china the Fuzhou transgression took place in the Late Pleistocene and the Changle transgression in the Holocene. The transgressions correspond to warm periods and regressions to cold periods. The younger transgressions were not only of shorter duration, but also of larger magnitude. These findings point to the existence of four flood event strata since the Middle Pleistocene: two in the late Middle Pleistocene and another two in the Late Pleistocene.

关键词： Quaternary marine transgressions palaeoclimate eastern china

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